OrganizationActive
William C Sim MD
NPI 1184431181 · Internal Medicine Physician · Fullerton, CA
William C Sim MD is a Internal Medicine Physician organization in Fullerton, CA (NPI 1184431181).
Provider details
- NPI number
- 1184431181
- Entity type
- Organization
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Organization subpart
- No
- Authorized official
- William Sim, President(562) 237-8761
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
Established profile(55/100 index)
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
1 yr in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
Practice location
3111 Santa Rosa Pl
Fullerton, CA 92835-1522
Phone: (562) 237-8761
Street-level locationGet directions
Mailing address
3111 Santa Rosa Pl
Fullerton, CA 92835-1522
Registry dates
- Enumerated
- 2024-12-12
- Last updated
- 2024-12-12
- Certified
- 2024-12-12
Frequently asked questions
- What is William C Sim MD's NPI number?
- William C Sim MD's National Provider Identifier (NPI) is 1184431181, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What type of organization is William C Sim MD?
- William C Sim MD is classified in the NPPES registry as Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is William C Sim MD located?
- William C Sim MD's practice location on file with NPPES is 3111 Santa Rosa Pl, Fullerton, CA 92835-1522.
- What is William C Sim MD's phone number?
- The practice phone number listed in the NPPES registry for William C Sim MD is (562) 237-8761.
- Who is the authorized official for William C Sim MD?
- The authorized official listed on William C Sim MD's NPPES record is William Sim, President. The authorized official registers and maintains the organization's NPI and is not necessarily its owner.
- Is William C Sim MD's NPI active?
- Yes — William C Sim MD's NPI (1184431181) is active in the NPPES registry as of the last update on 2024-12-12.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.